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Why is Firefox HAR data page timings for onContentLoad and onLoad equal to -1

  • 3 replies
  • 1 has this problem
  • 60 views
  • Last reply by Shadow110

jimmy-ly00
jimmy-ly00

I'm testing the network performance of my website and I need to export a few samples of it. From the Firefox Dev Tools, I can "Save All As HAR", but viewing the contents the page timings is wrong.

Here is a sample of the HAR file and I am using Firefox 54.0.1: 

   "pages": [
     {
       "startedDateTime": "2017-07-22T14:47:49.001+01:00",
       "id": "page_6",
       "title": "Mid-Latency",
       "pageTimings": {
         "onContentLoad": -1,
         "onLoad": -1
       }
     }
   ],

1. Why is the pageTimings = -1 and not (for example) 500ms? 2. Where is the waterfall data of each resources and timings?

I'm testing the network performance of my website and I need to export a few samples of it. From the Firefox Dev Tools, I can "Save All As HAR", but viewing the contents the page timings is wrong. Here is a sample of the HAR file and I am using Firefox 54.0.1: "pages": [ { "startedDateTime": "2017-07-22T14:47:49.001+01:00", "id": "page_6", "title": "Mid-Latency", "pageTimings": { "onContentLoad": -1, "onLoad": -1 } } ], 1. Why is the pageTimings = -1 and not (for example) 500ms? 2. Where is the waterfall data of each resources and timings?

Chosen solution

It seems to be a bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1174091

An alternative solution of getting the onLoad I've found, is to get the difference between the startedDateTime and add the last entry "time".

Not sure why this is the case, but I guess it will have to do. Can I get this closed?

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All Replies (3)

Shadow110
Shadow110

Beyond most of us here. Have you tried other sites : https://confluence.atlassian.com/kb/generating-har-files-and-analysing-web-requests-720420612.html

https://stackoverflow.com/

jimmy-ly00
jimmy-ly00 Question owner

Chosen Solution

It seems to be a bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1174091

An alternative solution of getting the onLoad I've found, is to get the difference between the startedDateTime and add the last entry "time".

Not sure why this is the case, but I guess it will have to do. Can I get this closed?

Shadow110
Shadow110

Yes you can. Mark your reply as solved/helpful or..

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